Knock-down grille construction



Oct. 17, 1939. M, s, @BSCN KNocK-DowN GRILLE CONSTRUCTION 4 Sheets-Sheet 1 Filed June 4, 1936 Oct. 17, 1939. M. s. GIBSON KNOCK-DOWN GRILLE CONSTRUCTION Filed June 4, 1936 4 Sheets-Sheet 2 ,9 O ovnezL Oct. 17, 1939. I M; s G|B5QN 2,176,334

KNOCK-DOWN GRILLE CONSTRUCTION v Filed June 4, 1936 4 Sheets-Sheet 3 Oct. 17, 1939. M. s.- GIBSON KNOCK-DOWN GRILLE CONSTRUCTION Filed June 4, 1936 4 Sheets-Sheet 4 Imfen or /IU AQZSW? omen bars and the like used by criminals.

Patented Oct. 17, 1939 UNTE STATES PATENT CFFICE KNOCK-DOWN GRILLE CONSTRUCTION Application June 4, 1936, Serial No. 83,438

38 Claims.

; window openings of varying sizes.

Unlawful entriesI into buildings and homes for commission of burglaries and other numerous crimes have become so common and general as to necessitate the adoption of exclusion devices capable of resisting the numerous and ingenious tools employed by criminals' without, however, destroying or impairing the appearance, ventilation and other desirable characteristics of dwellings in particular, and other buildings proportionately to the desirability of preserving such characteristics as in stores, banks and other in stitutions frequented by large numbers of patrons.

The most vulnerable points of entry are presented by the windows and doors of buildings, obviously, and in the case of windows in particulanand doors to an appreciable extent, ineicient locks and structural characteristics afford means offering little resistance to forcible yet noiseless intrusion into premises.

Experience has demonstrated that even the unsightly steel doors and window closures commonly used on buildings of many types are relatively ineicient because of the lack of strength of the materials of which they are composed. Similarly, the prison-type steel bars and grilles commonly used on basement and other easily accessible windows have been of little exclusion value because of their lack of sufficient resistance to the excellent saws, files and miniature crow- However, the metal door and window guards have been demonstrated to afford better protection than any other types of exclusion means, but by reason of the great variations in sizes of doors and windows and particularly the doors and windows of dwellings, the metallic guards heretofore and now most commonly employed are required to be custom-made in factoriesand, therefore, are far too expensive to fall within the purchasing power 1 of the average home owner. rihis is especially true of such devices if made of a metal such as high-grade steel, capable of offering the requisite resistance to hack saws and other burglar tools.

Sufficiently low cost of high-grade steel guards for doors and windows to reduce the investment therein of the average home owner to the degree indicated can be accomplished only by obviating the existing modes of manufacture thereof and converting production thereof into the mass type wherein the components of every guard are produced by automatic machinery and other cost economy equipment and wherein the assembly of components of structures of greatly varying dimension is easy and cheap of accomplishment.

A further important object of the invention is 5 to provide knock-down structures of the general type indicated which can be readily assembled by hand with ease and rapidity to produce resultant structuresI of sizes to t accurately window or door openings of different buildings and the cornponent parts of which are producible in one factory at low cost and warehoused at a variety of geographically advantageous points for assembly at said points or at the place of ultimate installation thereof thus to secure the most advantageous transportation charges and likewise the maximum production economies.

Another object of the invention is to provide knock-down structures of the type and possessing the desirable characteristics aforesaid which can be readily reconstructed to the extent necessary to increase or decrease the dimensions thereof, thus to enable a single one or a set of said structures to be removed from one building and installed upon another without incurring great expense.

A further particular object of the invention is to provide a knock-down structure of the type specified which is so constructed as to provide requisite strength while reducing its light-excluding properties to the minimum and rendering the same ornamental.

Other objects and advantages of the invention are set forth in detail or will be understood from the following specication.

Suitable embodiments of the invention are i1- lustrated in the accompanying drawings, where- 1n:

Fig. 1 is a front elevation of a protective structure constructed in accordance with the invention.

Fig. 2 is a fragmentary vertical longitudinal section of the same on an enlarged scale taken on the line '2e-2 of Fig. 1.

Fig. 3 is a fragmentary detail plan sectional view of the same on an enlarged scale taken on the line 3 3 of Fig. l.

Fig. 4 isl a fragmentary vertical sectional view of the structure on an enlarged scale taken on the line 4 4 of Fig. 5. 50

Fig. 5 is a fragmentary end elevation of same partly in section looking at the right hand side of the structure as shown in Fig. 4.

Fig. 6 is a side elevation of one of the vertical bars of the structure of Fig. 1.

Fig. 6a and Fig. 6b are plan sectional Views on lines Ela- 5a and en -6b of Fig. 6.

Fig. '7 isl a fragmentary detail plan on an enlarged scale showing a metal sleeve in section.

Fig. 8 is a fragmentary detail vertical sectional view taken on the line 8-3 of Fig. 7.

Fig. 9 is a view similar to Fig. '7 showing the vertical bar of the latter positioned at an angler of degrees from the position of said bar as shown in Fig. 7.

Fig. 10 is a fragmentary detail vertical sectional view taken on the line Iil--I of Fig. 9.

Fig. 11 is a fragmentary detail transverse sectional view taken on the line I I-I I of Fig. '7.

Fig. 12 is a fragmentary .detail plan sectional View taken on the line I2-I2 of Fig. 10.

Fig. 13 is a fragmentary detail vertical sectional View taken on the line I3--I3 of Fig. 9.

Fig. 14 is a fragmentary detail plan sectional view taken on the line Ill-I4 of Fig, 10.

Fig. 15 is a perspective view of a plug constituting an element of the structure of Figs. 'l to 14 inclusive.

Fig. 16 is a fragmentary detail perspective View partly in section showing a portion of the grille structure assembled with the marginal frame of the structure.

Fig. 17 is a perspective View showing a sleeve employed for locking the vertical members of the grille of the structure against engagement from the horizontal members thereof.

Fig. 18 is a fragmentary perspective view of component members of the marginal frame in its assembled relation to each other.

Fig. 19 is an enlarged perspective View of one of said component sleeve members of the marginal frame. l

Fig. 20 is a vertical sectional View partly in elevation showing a modified form of construction of the grille structure.

Fig. 21 is a fragmentary detail vertical sectional view taken on the line 2I-2l of Fig.. 20.

Fig. 22 is a fragmentary perspective View showing one end portion of the vertical bar of Fig. 20.

Fig. 23 is a perspective View of a plug employed in connection with the bar of Fig. 2.

Fig. 24 is a vertical sectional view showing the relative positions of the vertical bar and two of the horizontal bar structures of the device in the relative positions in which assembly thereof is eected prior to the relative positions of said respective members as shown in Fig. 20.

Fig. 25 is a perspective View of one of the sections of the horizontal bars of the grille structure intermediate the terminal sections thereof.

The structure embodying the invention comprises as one element thereof a marginal frame A which is composed entirely of hollow tubular sections.

These sections consist of corner or elbow members I, side rail sections 2 and end rail sections 3 all of which are rectangular in cross-section.

Said sections 2 and 3, respectively, are connected with each other by means of telescopic sleeve members (Fig. 18) each of which is first rigidly secured along one end portion thereof to one member 2 or 3 of any pair thereof in any suitable manner and its projecting end portion then inserted into the next adjacent member 2 or 3, as the case may be, and then suitably, but detachably, secured to the latter.

Each set of sections 2 and 3, respectively, employed together with sleeves 4 to make up a side rail or end rail of a marginal frame of given dimensions, is equipped with openings 5 and G,

respectively, in its inner wall, so spaced from each other in each section 2 and 3 and from the respective ends thereof as to cause all of the openings 5 in a completed side rail to be spaced equally from each other. This is true also of the openings 6 of the end rails. Similar openings are provided in the sleeves 4 to register with openings 5 and E, respectively, as shown.

Projecting portions of sleeves i at the respective ends of completed side and end rails engage in the corner members I. The inner walls of said corner or elbow members I are equipped with recesses l extending from the extremities of said walls a minimum distance which, in the case of the side rail portions of a frame of the particular type illustrated in Fig. 1, is of a length equal to or slightly greater than one-half the spacing apart of the openings 5. The reasons for this length of slot and other functions of the latter during assembly of a complete structure such as is shown in Fig. 1, will be better comprehended in connection with the description of the manner in which the assembly of all component parts of the structure is accomplished.

In the instance illustrated the grille or `foraminous panel per se of the structure of Fig. 1 is composed of horizontal bars spaced equally from each other and vertical connecting bars which are disposed in staggered relation to each other. The relative positions of said bars and connecting members or bars may be reversed, of course, but for purposes of this specification, they will be referred to in the positions in which they are illustrated in Fig. 1.

Before completing assembly of the marginal frame, such as is illustrated in Fig. l, it is necessary to complete assembly of the grille or foraminous panel B of the structure.

The latter is composed in the main of equal length sections 8 which make up the horizontal bars, and equal length connecting vertical bars 9 which are interlocked with said sections 8 to lock the latter against relative movement and which, when so interlocked with said sections 8 and after the extremities of the marginal bars 9 are anchored within the marginal A, are also prevented from being disengaged from said bars or sections 8. The terminal members le of the horizontal bars are also anchored in the marginal frame, the anchoring means for terminals I0 and marginal bars 9 being identical with each other and described hereinafter.

In the accompanying drawings there are illustrated two different embodiments of the invention insofar as the same relate to the construction of a knock-down grille or foraminous panel to be bordered by and secured to the frame A. Either of these embodiments may be substituted for the other as both function in substantially the same way to produce substantially the same result. The grille structure illustrated in Figs. 1 to 1'?, inclusive, is preferable to that illustrated in Figs. 20 to 24 inclusive for no other reason than that of the appearance of the completed structure whereas the structure of Figs. 20 to 2e inclusive is preferable because of lower cost of manufacture and assembly.

Referring first to Figs. 4, 8 and 10, it will be noted that the component sections 8 of the horizontal bars are out away at their opposite end portions to provide terminal flanges I I which are substantially one-half the thickness of the body portion of the said section. The extremities of said flanges II are bevelled or otherwise formed for engagement with the overhanging shoulders I2 disposed at the inner end of each flange II of each section.

The flanges II of each section 8 are staggered with relation to each other and each of said flanges completely overlaps a flange II of a companion section, the inter engagement of the bevelled ends of said flanges II cooperating with the shoulders I2 to prevent separation of said sections vertically, i. e., perpendicularly of the bar, with relation to each other.

Each section 8 is provided midway between its ends with a longitudinal slot I3 which, in the instance illustrated, is Oblong, but which may be of any suitable shape. Similar registering slots I4 are provided in the flanges I I, it being obvious, of course, that the outer extremities of the terminal sections 8 of said bars may not be provided with said slots I3. In the instance illustrated each terminal section 8 is provided at its outer extremity with a T-shaped head I5 for engagement with a channeled bar I6 disposed within a side rail of the marginal frame A. The said terminal sections 8 generally will be of shorter length and possibly one-half the length of the intermediate sections 8, the reasons for this being explained hereinafter.

Referring now to Fig. 6, there is shown, in elevation, one of the vertical bars 9. The latter preferably is of the same Width as the sections V8 and adjacent its ends, said bar 9 is provided with side recesses I1 the length of each of which is equal to the outer vertical dimension of the sleeve I8. The resulting necks bordered by the said recesses I I are initially substantially square in cross section and are then bevelled or cut away angularly at two diagonally opposite corners I9 as more particularly shown in Figs. 6a in the upper neck. It will be noted that the neck shown in Fig. 6b has the cut away corners or bevels 20 which are ninety degrees removed from the corners I9 shown in Fig. 6a. Said necks are also then cut away between their ends to form cylindrical portions 2| which are coaxial at opposite ends of the bar.

The plugs 22 are disposed upon the necks of the bars 9 With their outer faces flush with the outer peripheral faces of the heads of the bars 9 and are carried into the slots of bars 8 as the head ends of bars 9 are passed through said slots. As insertion of a bar 9 through a slot of a bar 8 is effected, the bar 9 is rotated through an arc of degrees about its own axis in the direction permitted by the bevel faces 20 of the neck of bar 9 to position shown in Figs. 9 and 10.

l The plugs 22 having been first mounted upon the other neck of bar 9, the latter is inserted through slot of second bar 8 while the latter is disposed at an angle of 90 degrees in the direction permitted by bevel faces 28. When this has been accomplished the plugs 22 are trapped in the slots of bars 8 and after assembly of a row of bars 9 with the requisite bars 8, the latter are anchored at their ends in the channel bars of the marginal frame, this anchoring being effected only when the whole panel has been assembled. When so anchored the bars 8 at one elevation cannot be rotated relatively to the remaining bars 8, obviously. And because of the relative positions of the bevel faces 2U at right angles to each other at opposite ends of each bar 9, the latter cannot be rotated relatively to the bars 8 engaged therewith because in attempting to do this the slots in bars 8 would require to be sprung to too great a width to permit a right angle corner of a neck of said bar 9 to reach the position of Figs. 7 and 8.

Two side faces of the necks aforesaid are flush with the side faces of the body of the bar 9 and the other side faces extend perpendicularly to the said side faces of the bar 9 and are of the same length as the first-named fiat faces of said necks.

Plugs 22, shown in Fig. 5 and each of which constitutes a normally rectangular block of metal, are provided at opposite ends of one face thereof with arcuate recesses 23 which define cross ribs 24. Said plugs 22 are of the same width as the thickness of the bar 9 and practically fill the recesses II in the respective end portions of said bar 9, the ribs or flanges 2liV being disposed in contact with the cylindrical portions 2I of said necks and being engaged along their upper and lower faces by the end portions of the polygonal parts of said necks.

The cross sectional dimensions of the bar 9 are so nearly equal to the length and width of the several slots in the sections 8 of the first-mentioned bars as to be capable of passing snugly telescopically through said slots. Sheet metal sleeves 25, such as are shown in Fig. 17, are disposed over the slotted portions of the sections 8 with the slots 29 of said sleeves 25 disposed in alignment or flush with the slots of said horizontal bars composed of said sections 8.

Referring to Fig. 1, it will be readily understood that in assembling the sections 8 and4 I0 of the horizontal bars progressively with bars 9, the primary operation will be to connect an upper terminal bar 9 with a section 8 by passing the lower end of said bar 9 through a slot I3 of a section 8. Said end portion necessarily also passes through the slots 26 of the sleeve 25. If, for example, said bar 9 is already engaged with the channeled retaining member I5 in the upper end rail 3 of the marginal frame A, then at the time of passing said lower end of said bar through said slots, as aforesaid, the said section 8 must be turned ninety degrees from the position shown in Fig. 1 before the lower end of said bar 9 can be passed through said slot I 3, The said section 8 would then be turned through an arc of ninety degrees in the ydirection permitted by the bevelled portion 20 of the neck of the bar 9 with which said section 9 is engaged.

In the instance illustrated the other of the two upper bars 9 would be similarly engaged with a second section 8 and when said sections 8 are disposed in the positions shown in Fig. 1 with the bars 9 properly spaced from each other, said sections 8 overlap each other midway between the two bars 9.

It will be noted by reference to Figs. 8, 16 and 17 that each of the sleeves 25 is equipped along one end of each of the slots 26 therein, with an upstanding flange 2'I. The length of each -slot 26 is equal to the width of the bar 9 plus a distance equal to the length of a bevel I9 or 20 as the case may be, of a neck of the bar 9. As indicated at 28 in Fig. 17, the flange 21 includes an angular projection 29, the angular face of which becomes opposed to and parallel with the angular wall 28 of the slot 26 when said flange is bent to lie within the slot 29 as shown in Fig. 16.

The plugs 22 may be composed of case iron and, if so, it would be possible to remove them forcibly by means of a sharp heavy blow which would break the cross-rib 24. The removal of the plugs 22 would produce no other result than to permit sections 8 to be moved longitudinally with relation to each other without thereby permitting u them to bedisengaged from each other or from bars 9.

The .sleeves 25, composed of a very tough metal, function to prevent ready access to the said plugs 22 but are used mainly to enhance the appearance of the grille.

As the end portion of a bar 9 is passed through a slot of a section 8 or through the slot I4 eX- tending through overlapped portions of sections 8, the sleeve 25 will be so disposed as to permit the bar to pass through said slot. After said bar 9 and section 8 have been rotated relatively to each other through an arc of ninety degrees, as above described the said sleeve 25 will be moved so that the angular Wall 23 of each slot 26 will abut against bevel I9 or 29, as the case may be, of the neck of the bar 9 in question. The flanges 21 are then bent downwardly to lie Within the slots 2B, the angular projections 29 being .sprung under the adjacent portion of the head of the bar 9 as more particularly shown in Fig. 16.

It will be obvious, of course, that after the sections 8 and 9 are disposed in the position of Fig. 1 and the terminal bars 9 are anchored in the channel I6, and further, after the next succeeding set of bars 9 are engaged with the rst-mentioned set of sections 8, that all relative rotation of the terminal bars 9 relatively to the bars 8 with which they are engaged will be rendered impossible because the side walls of channel I6 will not yield suihciently to permit this.

In assembling the bars 8 and 9 with each other as herein before described, the side walls of the slots I3 or I4 will spring sulrciently to permit the relative rotation of bars 8 in one direction relatively to a bar 9.

In further assembly of the structure, the upper end portions of the next succeeding set of bars 9 will be rst passed through slots Ill in the overlapped end portions of the sections 8 of the uppermost horizontal bar in the same manner as has been described above with reference to the rst pair of said bars 9. Then, by means of a Wrench, said second set of bars 9 will be turned through an arc of ninety degrees to the position shown in Fig. l and thereafter the next lower set of sections 8 will be engaged with lower end portions of said bars 9 through the slots I3, said lastmentioned sections 8 being then disposed in position ninety degree from those shown in Fig. 1. In turning the last-mentioned sections 8 to the position shown in Fig. 1, their rotation will be opposite to that of the last-mentioned rotation of the bar 9, namely in the direction permitted by the bevel 29 of Fig. 6b. After the last-mentioned set of sections 3 are associated and interlocked with each other by means cf the next lower set of bars 9 and the ends of the complete articulate lower bar last referred to are anchored in the side rails of the marginal frame, the said second set of bars 9 cannot possibly b-e rotated relatively to the horizontal bars which they couple, so that the components of the structure are absolutely interlocked with each other against relative movement in all directions.

In connection with the last-mentioned description of the method of progressive assembly of bars 9 with sections 8 reference may be had t0 Figs. 7 to 14 inclusive.

`Each member 8 of the completed structure is engaged and interlocked with two other sections 3 and with at least one bar 9, and each bar 9 is engaged and interlocked with three sections 8, the exceptions being found only in the uppermostand lowermost set of bars 9 which may be engaged with only one or two sections 3 or with the overlapped end portions of two sections 8. Each of the terminal sections i9 is engaged with at least one section 8 and a bar 9 and, at its outer end With a channel member I6.

It will be appreciated, of course, that the Whole grille structure consisting of the sections and bars 9 Will be completed before the marginal frame is associated with said grille structure.

In the instance illustrated in Fig. 1, the side rails 2 cf the marginal frame A consist of two sections each, Whereas, the end rails are shown to comprise a single section each.

Referring now to Fig. 18, and also to Fig. 4, it Will be noted that the side rail sections of the frame A are provided, in their inner walls, with the openings 5 spaced from each other a distance equal to the spacing apart of the horizontal bars of the structure. Also, that said openings 5 correspond in shape with the cross sectional shape of said bars 9. Before the corners I become engaged with side rails 2 and after the latter have been built up to the desired length, the said terminal sections 8 of the grille structure are passed through said openings 5. The channeled members I9 are then inserted into the sidel rails through one or both ends of the latter and into engagement wtih the T-shaped heads of the terminal sections 8 so that all of said heads will be engaged by such channels. The latter are provided at intervals with threaded openings in which the Shanks of the adjusting screws 39 engage. The said screws extend through openings in the outer walls of said side rails and, wherever necessary, extend also through openings in the sleeves 9. After the side rails, or electively, the end rails, have been engaged with the terminal or marginal members of the grille structure, the corner sections will be engaged with said side and end rails in any selective order.

The terminal bars 9 are passed through openings 6 in the end rails and their heads are then similarly engaged with. a channel or channels I6 engaged with adjusting screws 39. Loosening of the screws 39 so that they barely engage in the threaded openings of the channeled bars I9 allows ample latitude for relative movement of the corner section and said side and .end rails to permit the assembly of corner section andv side and end rails to be readily accomplished, and

particularly because of the recesses I in inner walls cf said corner sections.

Following the complete assembly of the marginal frame A, as last-above described, the screws 99 along the side rails of the frame A will be rotated until the portion of the grille between the side rails has been adjusted so that the adjacent bars 9 at each side of the grille structure will be equally spaced from and parallel with the side rails of frame A.

Then the screws 39 in the end rails will be similarly manipulated so that the horizontal bars nearest adjacent said end rails will be maintained parallel with the latter, it being advisable to tighten all of the screws 99 sc that the whole grille structure is under tension both longitudinally and laterally thereof. When this has been accomplished it is impossible, obviously, to move the corner sections relatively to the side and end rails of the marginal frame. However, for purposes of greater security, the screws 3| are provided which engage in threaded openings in portions of sleeves 9, which project into the arms of each section I as shown particularly in Fig. 4.

As shown in Fig. 5, one or more of the screws y3| pass through slots 3Ia in the outer walls of the corner sections I for purposes of necessary adjustments to cover fractions of the constant spacings of the horizontal and vertical bars of the grille structure.

Generally speaking, the net internal width of the Side rail sections will be equal to or slightly greater than one-half the length of the terminal sections Il) and terminal end portions 8 of the horizontal bars, and also one-half the length of the bars 9, but if the latitude of adjustments of channel bars I6 proves insufficient to meet requirements, all of the terminals I and terminal sections 8 may be interchanged with shorter members. If we assume the length of each intermediate section 8 to be eight inches and the length of the terminal sections to be four inches, then by reason of the inner width of the side rail sections at both sides of the grille structure a total latitude of adjustment approximating four inches is allowed. The spacing apart of bars 9 is always equal to the length of a section 8 other than a terminal one. The net length of bars 9 from neck to neck thereof is equal to 'the space between opposed faces of a pair of horizontal bars. In the instant example, four inches constitutes the constant dimension governing the number of component Sections 8 and 9 required to build up a structure to nt the opening to be protected and the adjustments via screws 39 constitute the variable dimensions.

Similarly, the spacing apart of the horizontal bars may be four inches and the inner width of the end rails may be one-half said spacing or two inches, thereby allowing a sufficient latitude of adjustment both longitudinally and laterally of the grille structure to enable full length bars 9 to be employed to provide an ultimate assembled structure to fit window or door openings of a great number and practically all different sizes.

For purposes of appearance, on the one hand, and greater strength on the other, each of the corner sections is equipped wtih side plates 32 shown particularly in Fig. 2 and also in Fig. 18, which project beyond the ends of the respective arm of said corner sections I. Bracket plates 33 are also suitably secured to said corner sections I as shown in Fig. 18 for strengthening the same. Said brackets 33 and plates 32, preferably, are Welded to said corner sections.

In Figs'. 20 to 24 inclusive, there is illustrated a modified form of construction wherein the sections 8 of the horizontal bars are identical with those of Figs. 1 to 17, except that the slots 34 and 35 thereof, corresponding to slots I3 and I4 of the structure of Figs. 1 to 17 inclusive, terminate at one end in slightly bevelled walls 36.

In place of the bars 9 of Fig. 6, there are employed Z-shaped bars 31, the middle portions of which are of slightly greater thickness than the Width of the slots 34 and 35 to provide shoulders 38 against which the portions of' the `sleeves 39 bordering the slots 34 and 35 will abut when the heads 48 of said bars 31 are engaged with the body portions or overlapped flanges, respectively, of the sections 8 as more particularly shown in Fig. 20.

The structure of Figs. 20 to 24, inclusive, is extremely simple and the assembling of said structure will be readily understood by referring to Fig. 24, wherein two horizontal bars are shown as disposed in relatively displaced position longitudinally thereof. The said horizontal bars are first made up of a requisite number of sections to full predetermined length. Then said assembled bars are disposed relatively to each other so that one of the slots 34 or 35 of the pair thereof, through which the heads 4U are to be passed, is out of alignment with the companion slot of the adjacent horizontal bar to the extent necessary to permit the heads of a bar 31 to be passed through the said companion slots as Ishown in Fig. 24. v

By then moving the upper horizontal bar to the left and the lower one to the right until the 'oar 81 is disposed perpendicularly to both said horizontal bars, in the position shown in Fig. 20, the plugs 4I are dropped into the vacant portions of the slots as shown in Fig. and, thereupon, the flanges 42 bordering theA slots in the sheet metal sleeves 43 will be bent to the full lin'e position shown in Fig. 20. 4

In effecting the assembly of the grille coinposed of the sections 8 and 31, all of the component horizontal bars .are preferably rst loosely assembled and disposed successively in therelative positions of the two horizontal bars 'shown in Fig. y24. u y

All of the bars 31 are then disposed relatively to the horizontal bars as shown in Fig. 24 and thereupon the said horizontal bars are moved successively to their relative normal positions and all plugs 4I then dropped into place. The flanges 42 of the 'sleeves 43 are then bent to positions shown in Fig. 20, thereby completing the grille structure preparatory to mounting the marginal frame A thereon as described in connection with Figs. l to 17 inclusive, it being understood, of course, that all marginal sections 8 and bars 31 of Figs. 1 to 24 inclusive will be shaped for inserltion through openings: 5 and 8 respective of the marginal frame A and equipped at said ends With formations to engage adjusting means such as the channels I6 and screws 30 or equivalents thereof.

After the ends of the horizontal bars of the resulting grille structure are anchored by means of the channeled members I8 in the side rails of the marginal frame, it will be obvious that said horizontal bars cannot be restored by relative movement to any position approximating that of Fig. 24, and thus it will be impossible to disassemble the grille structure, even though the plugs 4I are removed, because the projecting portions of the heads 40 are of greater length than the plugs 4I.

From the foregoing description it will be apparent that after complete assembly of a structure embodying this invention has been effected, the marginal frame, per se and independently of the adjusting means contained therein, will serve to prevent disassembly of the grille structure and, on the other hand, the said adjusting means in the marginal frame A, when in position to hold the grille against all movement relatively to the said frame A, also functions to prevent disassembly of the components of said frame.

While the horizontal bars of the grille structure are illustrated and described as composed of sections each having a slot I 3 between its ends and slots I4 in its terminal flanges, it will be readily understood Without resort to further illustration, that the sections 8 may be one-half the length shown and overlapped with each other at the slots I3 also. In such event, each bar 9, except the marginal ones, would be interlocked with four sections of bars coupled thereby.

When said completed structure is tted into a window or door opening or a suitable window or door frame, the screws 36 and 3l are inaccessible to manipulation.

While I have illustrated and described only two embodiments of the invention herein, it will be understood, of course, that said invention is'` not limited to said several embodiments, but includes such embodiments as fall fairly within the denitions of the appended claims.

In the event that the horizontal bar sections 8 and lil are made in four inch lengths or multiples of four inches but so that each terminal end portion of each of said horizontal bars projects four inches from the vertical plane of the outermost vertical bars S, then the channel bars l5 need have no greater range of adjustment within the side rails of the marginal frame than two inches each in order to adjust the width of the whole structure to nt a window or door frame of an odd width, as for example, seventeen or eighteen inches or any fraction of four inches less than the maximum width to which the frame must be built up primarily to t the said window or door frame.

rlhis is true also with respect to the height of the window or door frame and the latitude of adjustment of the channels I6 in the end rails.

The width and length of the marginal frame A may be adjusted also to reduce the same down to any fractional part of four inches by employing the requisite short length side and end rail sections which will permit the corner sections l to move toward each other any fractional part of four inches. If said distance is less than four inches there will be a gap or gaps between opposed ends of side rail sections and corner sections and between opposed ends of corner sections and end rail sections which are covered and rendered invisible by the plates 32, the latter being, in the example presented, no less than four inches longer than the arms of the corner sections.

I claim as my invention:

1. A structure of the type specified comprising a foraminous panel equipped with marginal projections disposed vertically and horizontally, respectively, and each thereof provided adjacent its outer end with recesses, a knock-down marginal frame composed of tubular side and end rails, respectively, and hollow L-shaped corner sections each detachably engaged with an end portion of a side and an end rail, respectively, there being openings in the inner walls of said side and end rails and in the arms of said oorner sect-ions through which the end portions of said horizontal and vertical projections respectively of said panel extend, members within said marginal frame engaged with the recessed end portions of said projections of said panel, and manually operable means engaged with said members and the outer peripheral wall of said marginal frame for adjusting the position of said members within said frame to accord with the normal positions of the recessed end portions of said projections within said frame and imparting tension to said panel thereby to lock the latter into permanent engagement with said marginal frame and maintain the component rails and corner sections of the latter permanently interengaged with each other.

2. A structure of the type specified comprising a foraminous panel equipped with marginal projections disposed vertically and horizontally, respectively, a knock-down marginal frame composed of tubular side and end rails, respectively, and hollow L-shaped corner sections each detachably engaged with an end portion-of a side and end rail, respectively, there being openings in the inner walls of said side and end rails and in the arms of said corner sections through which the end portions of said horizontal and vertical rg.

projections respectively of said panel extend, and means engaged with the outer peripheral wall of the marginal frame and with the said projections of said panel for securing said panel to said frame and preventing disengagement of the corner sections of the latter from the side and end rails thereof.

3. A structure of the type specified comprising a foraminous panel equipped with marginal projections disposed vertically and horizontally, re-;

spectively, a knock-down marginal frame composed of tubular side and end rails, respectively, and hollow i,.-shaped corner sections each detachably engaged with an end portion of a side and end rail, respectively, there being openings ini the inner walls oi said side and end rails and in the arms of said corner sections through which the end portions of said horizontal and vertical projections respectively of said panel extend, and

manually adjustable means engaged with the por-f tions of said projections .disposed within the marginal frame and with the outer peripheral wall of the latter for drawing said projections toward said outer wall, thereby to subject said panel to permanent tension stresses vertically and horizontally thereof and thus also prevent disengagement of the corner sections from the side and end rails of the said marginal frame.

4. A structure of the type specified comprising a foraminous panel equipped with marginal projections disposed vertically and horizontally, respectively, a knock-.down marginal frame composed of tubular side and end rails, respectively, and hollow L-shaped corner sections each detachably engaged with an end portion of a side.`

and end rails, respectively, there being openings in the inner walls of said side and end rails and in the arms of said corner sections through which the end portions of said horizontal and vertical projections respectively of said panel extend, and,y

from said panel and subjecting the latter to per-.

manent tension stresses vertically and horizontally thereof and thus also prevent disengagement of the corner sections from the side and end rails of said marginal frame.

5. 'Ihe combination with a foraminous panel` structure of a knock-down hollow marginal frame structure adapted to receive the marginal portions of said panel structure, said frame structure comprising hollow side and end rails equipped with openings in their inner walls to receive the marginal portions cf said panel, corner sections detachably engaged with the ends of said side and end rails and provided with slots to receive corner portions of said panel, and means within said marginal frame engaged with and manually adjustable relatively to the walls thereof and detachably engaged with the marginal portions of said panel for adjusting the position of the latter relatively to said frame and securing the same thereto, said means acting also to prevent disengagement of said corner sections from the side and end rails of said frame.

6. The combination with a foraminous panel structure of a knock-down hollow marginal frame structure adapted toreceive the marginal por- Ail() tions of said panel structure, said frame structure comprising hollow side and end rails equipped with openings in their inner walls to receive the marginal portions of said panel and adapted to be moved relatively to each other and said panel to receive the marginal portions of the latter, devices adapted to be inserted into said rails from the ends thereof after positioning the same as aforesaid for engaging the marginal portions of 'the panel against disengagement from said rails,

rails.

7. A knock-down grille structure comprising a plurality of parallel spaced apart bars each composed mainly of sections of equal length overlapped with each other at their ends, there being slots extending through the overlapped end portions of said sections and a similar slot midway between the ends of each of said sections, the slots of each bar being disposed in alignment with slots of the next adjacent bar, connecting members equipped with heads at their opposite ends passed through said slots of two adjacent bars when the component sections of one of said bars are disposed out of their normal positions relatively to the component sections of the next adjacent bar and engaged against detachment from said component sections of both bars when in their relative normal positions and plugs disposed within and engaging the walls of said slots and portions of said connecting members for holding the latter against movement relatively to said bars longitudinally of said slots.

8. A knock-down grille structure comprising a plurality cf parallel spaced apart b-ars each composed mainly of sections of equal length overlapped with each other at their ends, there being slots extending through the overlapped end portions of said sections there being a similar slot midway between the ends of each of said sections, the slots in overlapped ends of each bar being disposed in alignment with slots between the ends of the next adjacent bar, connecting members extending at one end through pairs of aligned slots in overlapped bar sections and through said other slots at their other ends, said connecting members equipped with formations adjacent their respective ends engaged with opposite faces ci said bars bordering said slots thereby to prevent separation of overlapped portions of said bars in one direction and movement of said bars toward or from each other.

9. A knoclndown grille structure comprising a plurality of parallel spaced apart bars each composed mainly of sections of equal length overlapped with each other at their ends, there being slots extending through the overlapped end portions of said sections, the slots of each bar being disposed in alignment with slots of the next adjacent bar, connecting members extending through pairs of aligned slots of pairs of adjacent bars and equipped with formations adjacent their respective ends engaged with opposite faces of said bars bordering said slots thereby to prevent separation of overlapped portions of said bars in one direction and movement of said bars toward or from each other and plugs filling spaces in said slots not occupied by said members and cooperating with the latter to prevent relative longitudinal movement of com ponent sections of bars coupled by said members. 10. A knock-down grille structure comprising a plurality of parallel spaced apart bars each composed mainly of sections of equal length overlapped with each other at their ends, there being slots extending through the overlapped end portions of said sections and a similar slot midway between the ends of each of said sections, the slots of each bar being disposed in alignment with slots of the next adjacent bar, connecting members each projecting at one end through a slot extending through overlapped portions of sections of one bar and through a slot between the ends of a section of an adjacent bar, said members equipped with formations adjacent their respective ends engaged with opposite faces of said bars bordering said slots thereby to prevent separation of overlapped portions of said bars in one direction and movement of said bars toward or from each other.

11. A knock-down grille structure comprising a plurality of parallel spaced apart bars each composed mainly of sections of equal length overlapped with each other at their ends, there being slots extending through the overlapped end portions of said sections and a similar slot midway between the ends of each of said sections, the slots of each bar being disposed in alignment with slots of the next adjacent bar, connecting members each projecting at one end through a slot extending through overlapped portions of sections of one bar and through a slot between th-e ends of a section of an adjacent bar, said members equipped with formations adjacent their respective ends engaged with opposite faces of said bars bordering saidI slots thereby to prevent separation of overlapped portions of said bars in one direction and movement of said bars toward or from each other and plugs lling spaces in said slots not occupied by said members and cooperating with the latter to prevent relative longitudinal movement of component sections oi bars coupled by said members.

12. A knock-down grille structure consisting of a series of parallel spaced apart bars each composed mainly of equal sections overlapping each other at their ends, there being slots extending through overlapped end portions of said sections and a slot midway between the ends or each section, the first-named slots of one of said bars being aligned with the second-named slots of the next adjacent bar and connecting members extending through the pairs of aligned slots of pairs of adjacent bars and equipped with formations adjacent their respective ends engaged with opposite faces of said bars bordering said slots thereby to prevent separation of overlapped portions of said bars in one direction and movement of said bars toward or from each other.

13. A knockedown grille structure consisting of a series of parallel spaced apart bars each composed mainly of equal sections overlapping each other at their ends, there being slots extending through overlapped end portions of said sections and a slot midway between the ends of each section, the first-named slots of one of said bars being aligned with the second-named slots of the next adjacent bar and connecting members extending through the pairs of aligned slots of pairs of adjacent bars and equipped with formations adjacent their respective ends engaged with opposite faces of said bars bordering said slots thereby to prevent separation of overlapped portions of said bars in one direction and movement of said bars toward or from each other and plugs filling spaces in said slots not occupied by said members and cooperating with the latter to prevent relative longitudinal movement of component sections of bars coupl-ed by said members.

14. A knock-down grille structure consisting of a series of parallel spaced apart bars each composed mainly of equal sections overlapping each othei` at their ends, there being slots eX- tending through overlapped end portions oi said sections and a slot midway between the ends of each section, the first-named slots of one of said bars being aligned with the second-named slots of the next adjacent bar and connecting members extending through the pairs of aligned slots of pairs of adjacent bars and equipped with formations adjacent their respective ends engaged with opposite faces of said. bars bordering said slots thereby to prevent separation of overlapped portions o said bars in one direction and movement ci said bars toward or from each other, each of said bars being connected with two adjacent bars by connecting members disposed in staggered relation to each other.

15. A knock-down grille structure consisting of a series of parallel spaced apart bars each composed mainly of equal sections overlapping each other at their ends, there being slots extending through overiapped end portions of said sections and a slot midway between the ends of each section, th-e iirst-named slots of one of said bars being aligned with the second-named slots of the next adjacent bar and connecting members each projecting at one end through only those slots of one bar extending through overlapped end portions of the -component sections thereof and at their other ends projecting only through slots between the 'ends of component sections of an adjacent bar, each of said members equipped with formations adjacent their respective ends engaged with opposite faces of said bars bordering said slots thereby to prevent separation of overlapped portions of said bars in one direction and movement of said bars to- Ward or from each other.

16. A knock-down grille structure consisting of a series of parallel spaced apart bars each composed mainly of equal sections overlapping each other at their ends, there being slots extending through overlapped end portions of said sections and a slot midway between the ends of each section, the first-named slots of one of said bars being aligned with the second-named slots of the next adjacent bar and connecting members each projecting at one end through only those slots of one bar extending through overlapped end portions of the component sections thereof and at their other ends projecting only through slots between the ends of component sections of an adjacent bar, each of said members equipped with formations adjacent their respective ends engaged with opposite faces of said bars bordering said slots thereby to prevent separation of overlapped portions of said 'bars in one direction and movement of said bars toward or from each other and plugs filling spaces in said slots not occupied by said members and cooperating with the latter to prevent relative longitudinal movement of component sections of bars coupled by said members.

17. A knock-down structure of the type specified comprising a series of parallel bars each composed of a series of overlapped sections, there being slots in the overlapped portions of said sections and between the ends of each section, coupling bars extending transversely of said Yfirstnamed bars and each engaged at one end in one of the first-named slots oi one of the latter and in one of the second-named slots in an adjacent bar, formations at each end of each of the second-named bars cooperating with walls of said slots and surface portions bordering said slots for locking said sections against separation in all directions and preventing disengagement of said bars from each other, a marginal hollow frame equipped internally with adjustable devices for engagement with terminal sections of the firstnamed bars and terminals of marginal coupling bars and adapted to maintain all of said bars under normal tension, said `formations of said coupling bars cooperating with said adjustable devices for preventing disengagement ofthe latter from said sections.

i8. A knock-down structure of the type specied comprising in combination, a hollow marginal frame, adjustable devices mounted within the same, sets of relatively transversely disposed detachably interlocked members disposed Within and occupying the area bordered by said frame, the marginal members of said respective sets projecting into said marginal frame and being connected with said devices, the latter being positioned to impart tension to said respective sets of members and maintaining all of said members against disengagement from each other.

19. An articulate foraminous structure comprising a set of articulate bars extending in one direction and each composed of a plurality of normally separable sections, a set of bars extending laterally of said articulate bars and each engaged at opposite ends with two of the latter, said lateral bars equipped with interlocking formations cooperating with each other to maintain said sections of the articulate bars in predetermined connected relation to each other and maintaining said lateral bars engaged with said articulate bars, a hollow marginal frame provided with openings through which marginal portions of said t foraminous structure project, and adjustable means within said marginal frame engaged with end portions of said marginal portions of said foraminous structure for locking the same against withdrawal from said frame and applying force to said foraminous structure whereby relative disengaging movement of component parts thereof is prevented.

20. A knock-down marginal frame adapted to be made up to iit any desired size of window frame or the like which comprises equal corner members, and side and end rail members, each composed of a series of outer members of selected lengths and a substantially similar series of inner members disposed in staggered relation to the said outer members, there being registering openings in said inner and outer members through which devices for preventing their relative longitudinal movement are adapted to project and whereby the said outer members are adapted to be held against relative longitudinal movement, all of said outer and inner members being interchangeable with other similar members of different lengths whereby to build up rails of any desired lengths, the terminal end portions` of said rails being telescopically engaged with said corner members `for cooperation with the latter to complete the frame structure with respect to its length and breadth, means for rigidly securing the corner members to said rails, and a grille structure bordered by said frame and presenting marginal projections projecting through said aligned openings in said rails for locking the component sections thereof against relative movement.

21. A knock-down marginal frame for a knockdown grille structure of the type set forth, comprising side and end rails each composed of Atubular sections of respectively predetermined lengths, coupling sleeves telescopically engaged at opposite end portions with end portions of said tubular sections, there being openings in said sleeves and said sections registering with each other and adapted to receive marginal projections of said grille structure whereby to prevent relative movementof said sections and said sleeves, hollow corner members each engaged telescopically with end portions of sleeves projecting from ends of terminal sections of an end and a side rail for coupling the latter with each other, and means within the frame detachably engageable with the said -marginal projections of the grille structure.

22. A knock-down marginal frame for a grille structure of the type specified comprising end and side rails each composed of a plurality of tubular sections abutting against each other at their ends, couplingsleeves each telescopically engaged at opposite end portions with end portions of adjacentsections, there being openings in said sections and said sleeves registering with each other andthrough which marginal projections of said grille structure are adapted to project for prevent-5 ing movements of said sections relatively to said sleeves, substantially L-shaped hollow corner members telescopically engaged with terminal end portions of the side'and end rails, the arms of corner members being equipped With slots adapted to receive the marginal elements of the grill structure engaged in terminal end portions of said side and end rails for permitting said corner members to be adjusted relatively to the side and end rails and eifect adjustments of relative positions of the latter to control the lateral and longitudinal dimensions of the frame within the limits determined by the range of adjustability of said corner members relatively to said side and end rails and the width of the latter between their inner andv outer walls opposed to the marginal elements of ,thek grille structure.

23. A knock-down closure structure comprising a series of spaced-apart bars each composed of a plurality of links overlapped with each other at their ends, members extending tarnsversely of said bars and each thereof engaged at onerend with overlapped end portions of links thereof for locking the same against disengagement from each other, .each of said members being engaged at its other end With'a link of a contiguous bar rbetween the ends of said link and being thereby prevented from being disengaged from the overlapped end portions of said links of the firstnamed bar, and a marginal-frame having opposed rails engaged with the terminal links' of said bars and having its other rails engaged with the outer ends of members engaged at their inner ends with links of bars disposed nearest adjacent the lastnamed rails, said frame preventing all of said` ymembers and links from being disengaged from each other.

a plurality of links overlapped with each other at their ends, members extending transversely of said bars and each thereof engaged at one end with overlapped end portions of links thereof for locking the same against disengagement from each other, each of said members being engaged at its other end with another of said bars for preventing its disengagement from said links, and a hollow marginal frame engaged with the terminal links of said bars and with the ends of members engaged with links of bars nearest adjacent to two opposed rails of said frame for maintaining all of said links and members interengaged with each other, said frame internally equipped with manually adjustable means for imparting tension to said bars and said members.

25. A knock-down closure structure comprising a series of spaced-apart bars each composed of a plurality of links overlapped with each other at their ends, members extending transversely of said bars and each thereof engaged at one end with overlapped end portions of links thereof for locking the same against disengagement from each other, each of said members being engaged at its other end with a link of a contiguous bar said members and links from being disengaged 1 from each other, said frame equipped with means for imparting tension to said bars and said members.

26. A knock-down closure structure comprising a set of spaced-apart parallel bars each composed s of a plurality of separable sections, a set of bars extending transversely of and coupling the bars of the rst set with each other, said second set of bars and said sections of the first-named set thereof being equipped with interengaged formartions whereby said second set of bars couples the said sections with each other and is interlocked with said first-named set of bars when disposed transversely of the latter, and a hollow marginal frame equipped internally with adjustable means engaged with the terminal sections of the firstnamed bars and with outer ends of some bars of the second set for maintaining said respective sets of bars disposed transversely of each other and under tension.

27. A knock-down closure structure comprising a set of spaced-apart parallel bars each composed of a plurality of separable sections, a set of bars extending transversely of and coupling the bars of the first set with each other, said second set of bars and said sections of the rst-named set thereof being equiped with interengaged formations whereby said second set of bars couples the said sections With each other and is interlocked with said first-named set of bars when disposed transversely of the latter, and a hollow marginal frame receiving the outer ends of bars of both sets and equipped internally with adjustable means engaged therewith for ymaintaining said respective sets of bars disposed transversely of each other and against relative movement.

28.. A knock-down structure of the type set forth comprising a set of parallel spaced apart articulate bars each composed of a plurality of sections engaged with each other, a set of links extending transversely of said bars and each engaged at its ends with component sections of said bars for connecting the latter with each other at a plurality of points between their ends, links also maintaining the component sections of said bars against movement relatively to each other in one direction, a hollow marginal frame equipped with openings through which the ends of said bars project into the same and with openings into which the ends of some of the links project into the same, devices within said frame engaged with said ends of said bars and last-named links for preventing their disengagement from said frame, and means for adjusting the relative spacing apart of the side and end rails, respectively, of said frame for cooperation with said devices to maintain all of the component links and bar sections rmly in their predetermined relative positions.

29. A structure of the type specied comprising a hollow marginal frame composed of side rails, end rails and corner members, the latter being adjustable relatively to each other to vary the spacing apart of the side and end rails respectively from each other and thereby vary the size of the frame, means for securing the said several rails and corner members against relative movement, a grille panel structure composed of articulately interengaged separable members having its marginal portions projecting through openings into said side and end rails of said frame, and devices within the latter engaged with said marginal portion of said panel structure for preventing disengagement thereof from said frame and also preventing the component members thereof from being disengaged from each other.

30. A structure of the type specified comprising a hollow marginal frame composed of side rails, end rails and corner members, the latter being adjustable relatively to each other to vary spacing apart of the side and end rails respectively from each other and thereby vary the vsize of the frame, means for securing the said severalr rails and corner members against relative movement, a

- grille panel structure composed o f articulately interengaged separable members having its marginal portions projecting through openings into said side and end rails of said frame, and manually adjustable devices Within the latter engaged with said marginal portion of said panelstructure for preventing disengagementv thereof from said frame and also preventing the component members thereof from being disengaged from each other.

31. A closure structure comprising a panel equipped with marginal projections spaced from each other, a knock-down marginal frame for said panel comprising side and end rails'each composed of a plurality of telescopically interengaged sections provided with openings extending through telescopically overlapped component sections of said rails and through which said projections of the panel project into said rails thereby to cause said projections to prevent relative disengaging movements of said component rail sections, corner members telescopically and adjustably connected with the ends of said rails, and means within said rails engaged with said projections of said panel to prevent withdrawal of the latter from said openings in said rails.

32. A closure structure comprising a panel equipped with marginal projections spaced from each other, a knock-down marginal frame for said panel comprisng side and end rails each composed of ra plurality of telescopicallyinter-- engaged sectionsprvided with openings extend- 'ing through telescopically overlapped component sections of said rails and through which said projections of the panel project into said rails thereby to cause said projections to prevent relative disengag'ing movements of said component rail sections, corner members telescop-ically and adjustably connected with the ends of said rails, adjustable means Within said rails engaging with said projections of said panel to prevent withdrawal of the latter from said openings in said rails and effecting adjustment of the position of the panel relatively to the said rails and vice versa.

33. A closure structure comprising a panel equipped with marginal projections spaced from each other, a knock-down marginal frame for said panel comprising side and end rails each composed of a plurality of telesco'pically interengaged sections provided with openings extending through telescopically overlapped portions of said sections and spaced from each other equally with said projections and through which the latter project for locking `said sections against relative movement, corner members telescopically and adjustably connected with the ends of said rails and adjustable means within said rails engaged with said projections of said panel to prevent withdrawal of the latter from said openings in said rails and effecting adjustment of the position ofthe panel relatively to the said rails and vice versa, and means rigidly securing said corner members to said rails.

34. The combination with a knock-down panel structure composed of separable articulately interengaged rods and including spaced apart marginal projections, of a hollow marginal frame composed of corner members and side and end rails adjustably engaged with said corner members, each of said railsI composed of selectively interchangeable telescopicallyinterengaged sections of selectivelengths for determining the respective lengths of said rails, the latter provided with openings extending through telescopically overlapped component sections thereof and spaced from' each other equally with the projections of said panel and through which said projections extend into said rails for' locking said component sections against disengagementY from each other, and means within the frame engaged with said projections for preventing disengagementv of the'latter from said frame and thereby preventing disengagements of the component rods of the panel from each other.

35. The combination with a knock-down panel structure composed of separable articulately interengagedro'dsand including spaced apart marginal projectionsof a hollovvmarginal frame composed or corner members and side and end rails adjustably engaged with said corner members, each of said rails composed of selectively interchangeable telescopically interengage'd sections of selective lengths for determining the respective lengths of said rails, ythe latter provided with openings extending through telescopically overlapped component sections thereof and spaced from each other equally with the projections of said panel and through which said projections eX- tend into said rails for locking said component sections against disengagement from each other and adjustable .devices within the frame engaged with said projections for preventing disengagement of the latter from said frame and thereby preventing disengagement of the component rods of the panel from each other and effecting adjustment of the relative positions of the panel and frame.

36. In combination, a marginal frame including side and end rails composed of telescopically interengaged hollow sections equipped with openings extending through telescopically overlapped portions of said sections, a panel member composed of sets of rods extending angularly of each other and articulately and detachably connected with each other and including marginal rods projecting through openings for preventing disengagement of the component sections of the said rails from each other, said openings cooperating with said marginal rods to maintain the component rods of the panel member in relative positions wherein they are maintained in interengaged relation to each other and devices Within said rails engaged with the outer end portions of said marginal rods for preventing their withdrawal from said openings.

37. In combination, a marginal frame including side and end rails composed of telescopically interengaged hollow sections equipped with openings extending through telescopically overlapped portions of said sections, a panel member composed of sets of rods extending angularly of each other and articulately and detachably connected with each other and including marginal rods projecting through openings for preventing disengagement of the component sections of the said rails from each other, said openings cooperating with said marginal rods to maintain the component rods of the panel member n relative positions wherein they are maintained in interengaged relation to each other, and adjustable devices within said rails engaged with the outer end portions of said marginal rods for preventing their withdrawal from said openings and imparting permanent stresses upon the panel member to prevent all relative movements between the component rods thereof.

38. A knock-down closure structure comprising a hollow marginal frame composed of side and end rails, and corner sections telescopically and adjustably connected with the terminal portions of all of said rails for varying the dimensions of said frame, at least one pair of opposed rails of said frame being composed of interchangeable hollow sections of such selective lengths as may belrequired to render said rails of predetermined lengths, said sections abutting each other at their meeting ends, coupling means disposed within said rails in staggered relation to said sections for maintaining the latter in axial alignment with each other, there being equally spaced apart openings in said rails all of which are spaced from the meeting ends of the component sections thereof and at least some of which are overlapped by said coupling means and aligned with openings in the latter, a plurality of parallel knock-down articular bars projecting at their opposite end portions into said openings, and adjustable anchoring devices within said rails detachably engaged with said end portions of said bars and adapted to maintain the same against disassembly.

MILO S. GIBSON. 

